| 摘要 |
To reduce unnecessary interference occurring between various types of signals. A circuit substrate (10) where a duplexer is mounted. A substrate body (12) includes main surfaces (S1, S2). External electrodes (14a to 14c) are provided in the main surface (S1). External electrodes (16a to 16c) are provided in the main surface (S2). Signal paths (SL1 to SL3) connect the external electrodes (14a to 14c) to the external electrodes (16a to 16c), respectively. Ground conductors (22a, 22b) are embedded in the substrate body (12), and overlap with a mounting area (R) so as to contain the mounting area (R) where the duplexer is mounted, in a planar view seen from the z-axis direction. In a planar view seen from the z-axis direction, the signal paths (SL1 to SL3) extend from the inside of the mounting area (R) to the outside of the mounting area (R) between the main surface (S1) and the ground conductor (22b), pass through the outside of the mounting area (R), and are connected to the external electrodes (16a to 16c), respectively. |
